Dec 24, 2012 5:30pm PST
. sloan foundation. supporting science, technology, and improved economic performance and fincial literacy in the 21st century. >> and with the ongoing support of these institutions and foundations. and... this program was made possible by the corporation for public broadcasting. and by contributions to your pbs station from viewers like you. thank you. >> brown: gunfire tore at the nation's holiday mood again today, with the emotional wounds from a school massacre still fresh. there were more fatal shootings, including one in western new york, where an attacker lay in wait for a fire crew. >> responding firefighters when they pulled up on the scene started receiving -- were fired upon. >> police speaking shortly after a home and car erupted in flames. it was arson they said later that turned out to be an ambush. >> it does appear that it was a trap that was set. for responding frst responrs. >> gunmen killed two volunteer firefighters and wounded two others then killed himself. police identified him as william spangler, he haddon time, 17 years for manslaughter but ha motive for today'